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91.
论大学物理实验体系建设与教学改革 总被引:2,自引:1,他引:2
传统的物理实验是按普通物理、电子线路和近代物理等内容进行划分,这种体系突出了学科的系统性,但忽视了学科之间的兼容互补性,各学科相互独立,限制了学生跨学科思维能力和创新能力的培养,建立现代物理实验教学新体系是大学物理实验教学改革的必然趋势.新的物理实验体系应依照训练层次,划分为引导性实验、基本实验、综合性实验、设计性实验、研究性实验.并需要注重时代性和先进性,改革和更新大学物理实验教学内容,改革实验教学与管理模式,形成新的运行机制,从而达到学生素质和能力的提高. 相似文献
92.
93.
研制了一种基于微通道板的超快脉冲中子探测器,对其γ射线灵敏度进行了理论和实验研究。建立了探测器的γ射线灵敏度理论计算模型,利用蒙特卡罗方法模拟计算了不同能量γ射线在不同厚度聚乙烯靶中产生的出射电子能谱和出射角度分布,并结合经验公式计算了单个电子在微通道板(MCP)孔道中产生的二次电子产额,最后得到了探测器的γ射线灵敏度,结果表明当聚乙烯靶厚度大于某一值时,γ射线灵敏度基本相同。利用西北核技术研究所的标准γ射线放射源对探测器的γ射线灵敏度进行了实验标定,实验结果与理论计算结果一致。 相似文献
94.
Crisólogo Dolores Flores Martha Iris Rivera López Deborah Moore-Russo 《School science and mathematics》2020,120(2):104-115
Slope is a fundamental mathematics concept in middle and high school that transcends to the university level. An understanding of slope is needed at the university level since slope plays an important role in understanding problems involving variation and change. In this study Mexican curricula documents were examined to determine which conceptualizations of slope are addressed in the intended mathematics curriculum. To explain the results, we use conceptualizations of slope identified in previous research. Our findings reveal that, to a certain extent, the conceptualizations proposed in the Mexican intended mathematics curriculum differ slightly in terms of the emphasis and timing of instruction from what others have identified in the U.S., with slope as a geometric ratio receiving less emphasis in the Mexican curriculum. There was also noted discontinuity within the Mexican curriculum in introducing slope in grade 9 and subsequently introducing of linear functions in grade 10 without explicit mention of slope. Suggestions are made for future studies, both to consider the conceptualizations of slope promoted in the Mexican textbooks and the impact they have in classroom instruction and student learning of slope. 相似文献
95.
Problem solving has long been a priority in mathematics education, and the first Common Core mathematical practice (SMP1) focuses on this priority through the language of “Make sense of problems and persevere in solving them.” We present findings from a survey about how prospective elementary teachers' (PTs) make sense of potential difficulties with fostering SMP1. Findings suggested that PTs' common anticipated difficulties relate to planning a solution pathway and self monitoring whether the solution makes sense. Moreover, a third of PTs disclosed that their anticipated difficulties are linked to their own personal struggles with aspects of SMP1. An alternative interpretation of SMP1 surfaced in which a small number of PTs described SMP1 as necessitating that a teacher teach multiple solution methods to students, instead of engaging students in productive struggle to develop their own strategies. We present a framework illustrating the connections between SMP 1 and Pólya's problem solving phases, and we discuss how these findings connect to and build on previous research of PTs' experiences with problem solving. We offer implications for the targeted support needed in teacher preparation programs to address these struggles, to prevent them from being replicated in their students. 相似文献
96.
Daniel Lee McGee Funda Gonulates Theodore Hodgson Meredith Brewer 《School science and mathematics》2020,120(4):220-231
This article presents a large-scale longitudinal study of hundreds of students across the state of Kentucky that participated in a dual-focus mathematics intervention initiative when they were in the third grade. Rather than an exclusive focus on intervention, this initiative focused on both (i) high quality pull-out intervention and (ii) coherence between pull-out intervention and classroom instruction. The study found that over half of the third grade intervention students that participated in this initiative were classified as “novice” (the lowest possible performance category) on state standardized mathematics assessments at the end of the third grade. However, over the course of the following four years, the novice reduction rate of these students was significantly (p < .01) greater than other novices in Kentucky that did not participate in the initiative. These findings indicate that when implementing intervention initiatives to help students that are struggling with mathematics, it may be important to establish coherence between pull-out intervention and classroom instruction. The long term impact of this approach among traditionally underrepresented minorities suggest that this publication may provide insight into important equity issues where long-term analyses may sometimes be needed to capture the full impact of intervention initiatives. 相似文献
97.
Noelia Santamaría-Cárdaba 《School science and mathematics》2020,120(8):467-476
This study brings together the research focused on science education through project-based learning (PBL). This learning project was carried out in a rural learning community and an attempt was made to adapt to the natural resources of the area by organizing educational outings, experimental activities, and encouraging the participation of families. The overall objective is to test the effectiveness of applying the PBL teaching methodology for learning science in a rural learning community. The methodology used has been qualitative, specifically, the participating research has been used and the information has been compiled in a field notebook. The results show that the didactic proposal had good results; showing that, in conclusion, science teaching today should be inclined toward more innovative educational methodologies such as PBL. 相似文献
98.
This study explores the grasp of square roots among eleven students in a remedial mathematics course, with a special focus on where the same student generated apparently conflicting responses. Building on the commognitive framework, the analysis distinguished between routines that individual students consistently implemented in situations where roots “stood alone” and where they were incorporated in more compound exercises, where roots were extracted from square numbers and from squared radicands, where roots were applied to monomials and binomials, and where parameters named with different letters were involved. Differences were found in routines’ degree of objectification, procedures, and tasks. These differences are explained with a theoretical account, suggesting that what may seem as a conflict within a student’s discourse could be a sensible difference of actions taken in situations that this student construed as different. The contribution of this study to the body of knowledge on teaching and learning of roots and to commognitive research is discussed. 相似文献
99.
光信息科学与技术专业实践教学的探索 总被引:2,自引:0,他引:2
在四年办学经验的基础上,探索了适合地方经济建设的光信息科学与技术的本科专业的实践教学体系,进一步提升了办学水平。 相似文献
100.
We study linearly ordered spaces which are Valdivia compact in their order topology. We find an internal characterization of these spaces and we present a counter-example disproving a conjecture posed earlier by the first author. The conjecture asserted that a compact line is Valdivia compact if its weight does not exceed ℵ1, every point of uncountable character is isolated from one side and every closed first countable subspace is metrizable. It turns out that the last condition is not sufficient. On the other hand, we show that the conjecture is valid if the closure of the set of points of uncountable character is scattered. This improves an earlier result of the first author. 相似文献